| Message ID | 20241222140247.174998-6-vaibhav@linux.ibm.com |
|---|---|
| State | New |
| Headers | show |
| Series | kvm powerpc/book3s-hv: Expose Hostwide counters as perf-events | expand |
On Sun, Dec 22, 2024 at 07:32:33PM +0530, Vaibhav Jain wrote: > Implement and setup necessary structures to send a prepolulated > Guest-State-Buffer(GSB) requesting hostwide counters to L0-PowerVM and have > the returned GSB holding the values of these counters parsed. This is done > via existing GSB implementation and with the newly added support of > Hostwide elements in GSB. > > The request to L0-PowerVM to return Hostwide counters is done using a > pre-allocated GSB named 'gsb_l0_stats'. To be able to populate this GSB > with the needed Guest-State-Elements (GSIDs) a instance of 'struct > kvmppc_gs_msg' named 'gsm_l0_stats' is introduced. The 'gsm_l0_stats' is > tied to an instance of 'struct kvmppc_gs_msg_ops' named 'gsb_ops_l0_stats' > which holds various callbacks to be compute the size ( hostwide_get_size() > ), populate the GSB ( hostwide_fill_info() ) and > refresh ( hostwide_refresh_info() ) the contents of > 'l0_stats' that holds the Hostwide counters returned from L0-PowerVM. > > To protect these structures from simultaneous access a spinlock > 'lock_l0_stats' has been introduced. The allocation and initialization of > the above structures is done in newly introduced kvmppc_init_hostwide() and > similarly the cleanup is performed in newly introduced > kvmppc_cleanup_hostwide(). > > Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com> > --- > arch/powerpc/kvm/book3s_hv_pmu.c | 189 +++++++++++++++++++++++++++++++ > 1 file changed, 189 insertions(+) > > diff --git a/arch/powerpc/kvm/book3s_hv_pmu.c b/arch/powerpc/kvm/book3s_hv_pmu.c > index e72542d5e750..f7fd5190ecf7 100644 > --- a/arch/powerpc/kvm/book3s_hv_pmu.c > +++ b/arch/powerpc/kvm/book3s_hv_pmu.c > @@ -27,10 +27,31 @@ > #include <asm/plpar_wrappers.h> > #include <asm/firmware.h> > > +#include "asm/guest-state-buffer.h" > + > enum kvmppc_pmu_eventid { > KVMPPC_EVENT_MAX, > }; > > +#define KVMPPC_PMU_EVENT_ATTR(_name, _id) \ > + PMU_EVENT_ATTR_ID(_name, power_events_sysfs_show, _id) > + > +/* Holds the hostwide stats */ > +static struct kvmppc_hostwide_stats { > + u64 guest_heap; > + u64 guest_heap_max; > + u64 guest_pgtable_size; > + u64 guest_pgtable_size_max; > + u64 guest_pgtable_reclaim; > +} l0_stats; > + > +/* Protect access to l0_stats */ > +static DEFINE_SPINLOCK(lock_l0_stats); > + > +/* GSB related structs needed to talk to L0 */ > +static struct kvmppc_gs_msg *gsm_l0_stats; > +static struct kvmppc_gs_buff *gsb_l0_stats; > + > static struct attribute *kvmppc_pmu_events_attr[] = { > NULL, > }; > @@ -90,6 +111,167 @@ static void kvmppc_pmu_read(struct perf_event *event) > { > } > > +/* Return the size of the needed guest state buffer */ > +static size_t hostwide_get_size(struct kvmppc_gs_msg *gsm) > + > +{ > + size_t size = 0; > + const u16 ids[] = { > + KVMPPC_GSID_L0_GUEST_HEAP, > + KVMPPC_GSID_L0_GUEST_HEAP_MAX, > + KVMPPC_GSID_L0_GUEST_PGTABLE_SIZE, > + KVMPPC_GSID_L0_GUEST_PGTABLE_SIZE_MAX, > + KVMPPC_GSID_L0_GUEST_PGTABLE_RECLAIM > + }; > + > + for (int i = 0; i < ARRAY_SIZE(ids); i++) > + size += kvmppc_gse_total_size(kvmppc_gsid_size(ids[i])); > + return size; > +} > + > +/* Populate the request guest state buffer */ > +static int hostwide_fill_info(struct kvmppc_gs_buff *gsb, > + struct kvmppc_gs_msg *gsm) > +{ > + struct kvmppc_hostwide_stats *stats = gsm->data; > + > + /* > + * It doesn't matter what values are put into request buffer as > + * they are going to be overwritten anyways. But for the sake of > + * testcode and symmetry contents of existing stats are put > + * populated into the request guest state buffer. > + */ > + if (kvmppc_gsm_includes(gsm, KVMPPC_GSID_L0_GUEST_HEAP)) > + kvmppc_gse_put_u64(gsb, KVMPPC_GSID_L0_GUEST_HEAP, > + stats->guest_heap); > + if (kvmppc_gsm_includes(gsm, KVMPPC_GSID_L0_GUEST_HEAP_MAX)) > + kvmppc_gse_put_u64(gsb, KVMPPC_GSID_L0_GUEST_HEAP_MAX, > + stats->guest_heap_max); > + if (kvmppc_gsm_includes(gsm, KVMPPC_GSID_L0_GUEST_PGTABLE_SIZE)) > + kvmppc_gse_put_u64(gsb, KVMPPC_GSID_L0_GUEST_PGTABLE_SIZE, > + stats->guest_pgtable_size); > + if (kvmppc_gsm_includes(gsm, KVMPPC_GSID_L0_GUEST_PGTABLE_SIZE_MAX)) > + kvmppc_gse_put_u64(gsb, KVMPPC_GSID_L0_GUEST_PGTABLE_SIZE_MAX, > + stats->guest_pgtable_size_max); > + if (kvmppc_gsm_includes(gsm, KVMPPC_GSID_L0_GUEST_PGTABLE_RECLAIM)) > + kvmppc_gse_put_u64(gsb, KVMPPC_GSID_L0_GUEST_PGTABLE_RECLAIM, > + stats->guest_pgtable_reclaim); > + > + return 0; > +} kvmppc_gse_put_u64() can return an error. I think we can handle it just like gs_msg_ops_vcpu_fill_info() > + > +/* Parse and update the host wide stats from returned gsb */ > +static int hostwide_refresh_info(struct kvmppc_gs_msg *gsm, > + struct kvmppc_gs_buff *gsb) > +{ > + struct kvmppc_gs_parser gsp = { 0 }; > + struct kvmppc_hostwide_stats *stats = gsm->data; > + struct kvmppc_gs_elem *gse; > + int rc; > + > + rc = kvmppc_gse_parse(&gsp, gsb); > + if (rc < 0) > + return rc; > + > + gse = kvmppc_gsp_lookup(&gsp, KVMPPC_GSID_L0_GUEST_HEAP); > + if (gse) > + stats->guest_heap = kvmppc_gse_get_u64(gse); > + > + gse = kvmppc_gsp_lookup(&gsp, KVMPPC_GSID_L0_GUEST_HEAP_MAX); > + if (gse) > + stats->guest_heap_max = kvmppc_gse_get_u64(gse); > + > + gse = kvmppc_gsp_lookup(&gsp, KVMPPC_GSID_L0_GUEST_PGTABLE_SIZE); > + if (gse) > + stats->guest_pgtable_size = kvmppc_gse_get_u64(gse); > + > + gse = kvmppc_gsp_lookup(&gsp, KVMPPC_GSID_L0_GUEST_PGTABLE_SIZE_MAX); > + if (gse) > + stats->guest_pgtable_size_max = kvmppc_gse_get_u64(gse); > + > + gse = kvmppc_gsp_lookup(&gsp, KVMPPC_GSID_L0_GUEST_PGTABLE_RECLAIM); > + if (gse) > + stats->guest_pgtable_reclaim = kvmppc_gse_get_u64(gse); > + > + return 0; > +} > + > +/* gsb-message ops for setting up/parsing */ > +static struct kvmppc_gs_msg_ops gsb_ops_l0_stats = { > + .get_size = hostwide_get_size, > + .fill_info = hostwide_fill_info, > + .refresh_info = hostwide_refresh_info, > +}; > + > +static int kvmppc_init_hostwide(void) > +{ > + int rc = 0; > + unsigned long flags; > + > + spin_lock_irqsave(&lock_l0_stats, flags); > + > + /* already registered ? */ > + if (gsm_l0_stats) { > + rc = 0; > + goto out; > + } > + > + /* setup the Guest state message/buffer to talk to L0 */ > + gsm_l0_stats = kvmppc_gsm_new(&gsb_ops_l0_stats, &l0_stats, > + GSM_SEND, GFP_KERNEL); > + if (!gsm_l0_stats) { > + rc = -ENOMEM; > + goto out; > + } > + > + /* Populate the Idents */ > + kvmppc_gsm_include(gsm_l0_stats, KVMPPC_GSID_L0_GUEST_HEAP); > + kvmppc_gsm_include(gsm_l0_stats, KVMPPC_GSID_L0_GUEST_HEAP_MAX); > + kvmppc_gsm_include(gsm_l0_stats, KVMPPC_GSID_L0_GUEST_PGTABLE_SIZE); > + kvmppc_gsm_include(gsm_l0_stats, KVMPPC_GSID_L0_GUEST_PGTABLE_SIZE_MAX); > + kvmppc_gsm_include(gsm_l0_stats, KVMPPC_GSID_L0_GUEST_PGTABLE_RECLAIM); > + > + /* allocate GSB. Guest/Vcpu Id is ignored */ > + gsb_l0_stats = kvmppc_gsb_new(kvmppc_gsm_size(gsm_l0_stats), 0, 0, > + GFP_KERNEL); > + if (!gsb_l0_stats) { > + rc = -ENOMEM; > + goto out; > + } > + > + /* ask the ops to fill in the info */ > + rc = kvmppc_gsm_fill_info(gsm_l0_stats, gsb_l0_stats); > + if (rc) > + goto out; > +out: > + if (rc) { > + if (gsm_l0_stats) > + kvmppc_gsm_free(gsm_l0_stats); > + if (gsb_l0_stats) > + kvmppc_gsb_free(gsb_l0_stats); > + gsm_l0_stats = NULL; > + gsb_l0_stats = NULL; > + } > + spin_unlock_irqrestore(&lock_l0_stats, flags); > + return rc; > +} The error handling can probably be simplified to avoid multiple ifs: <snip> /* allocate GSB. Guest/Vcpu Id is ignored */ gsb_l0_stats = kvmppc_gsb_new(kvmppc_gsm_size(gsm_l0_stats), 0, 0, GFP_KERNEL); if (!gsb_l0_stats) { rc = -ENOMEM; goto err_gsm; } /* ask the ops to fill in the info */ rc = kvmppc_gsm_fill_info(gsm_l0_stats, gsb_l0_stats); if (!rc) goto out; err_gsb: kvmppc_gsb_free(gsb_l0_stats); gsb_l0_stats = NULL; err_gsm: kvmppc_gsm_free(gsm_l0_stats); gsm_l0_stats = NULL; out: spin_unlock_irqrestore(&lock_l0_stats, flags); return rc; } > + > +static void kvmppc_cleanup_hostwide(void) > +{ > + unsigned long flags; > + > + spin_lock_irqsave(&lock_l0_stats, flags); > + > + if (gsm_l0_stats) > + kvmppc_gsm_free(gsm_l0_stats); > + if (gsb_l0_stats) > + kvmppc_gsb_free(gsb_l0_stats); > + gsm_l0_stats = NULL; > + gsb_l0_stats = NULL; > + > + spin_unlock_irqrestore(&lock_l0_stats, flags); > +} > + > /* L1 wide counters PMU */ > static struct pmu kvmppc_pmu = { > .task_ctx_nr = perf_sw_context, > @@ -108,6 +290,10 @@ int kvmppc_register_pmu(void) > > /* only support events for nestedv2 right now */ > if (kvmhv_is_nestedv2()) { > + rc = kvmppc_init_hostwide(); > + if (rc) > + goto out; > + > /* Setup done now register the PMU */ > pr_info("Registering kvm-hv pmu"); > > @@ -117,6 +303,7 @@ int kvmppc_register_pmu(void) > -1) : 0; > } > > +out: > return rc; > } > EXPORT_SYMBOL_GPL(kvmppc_register_pmu); > @@ -124,6 +311,8 @@ EXPORT_SYMBOL_GPL(kvmppc_register_pmu); > void kvmppc_unregister_pmu(void) > { > if (kvmhv_is_nestedv2()) { > + kvmppc_cleanup_hostwide(); > + > if (kvmppc_pmu.type != -1) > perf_pmu_unregister(&kvmppc_pmu); > > -- > 2.47.1 >
Hi Gautam, Thanks for reviewing this patch. My responses to your review comments inline below: Gautam Menghani <gautam@linux.ibm.com> writes: > On Sun, Dec 22, 2024 at 07:32:33PM +0530, Vaibhav Jain wrote: >> Implement and setup necessary structures to send a prepolulated >> Guest-State-Buffer(GSB) requesting hostwide counters to L0-PowerVM and have >> the returned GSB holding the values of these counters parsed. This is done >> via existing GSB implementation and with the newly added support of >> Hostwide elements in GSB. >> >> The request to L0-PowerVM to return Hostwide counters is done using a >> pre-allocated GSB named 'gsb_l0_stats'. To be able to populate this GSB >> with the needed Guest-State-Elements (GSIDs) a instance of 'struct >> kvmppc_gs_msg' named 'gsm_l0_stats' is introduced. The 'gsm_l0_stats' is >> tied to an instance of 'struct kvmppc_gs_msg_ops' named 'gsb_ops_l0_stats' >> which holds various callbacks to be compute the size ( hostwide_get_size() >> ), populate the GSB ( hostwide_fill_info() ) and >> refresh ( hostwide_refresh_info() ) the contents of >> 'l0_stats' that holds the Hostwide counters returned from L0-PowerVM. >> >> To protect these structures from simultaneous access a spinlock >> 'lock_l0_stats' has been introduced. The allocation and initialization of >> the above structures is done in newly introduced kvmppc_init_hostwide() and >> similarly the cleanup is performed in newly introduced >> kvmppc_cleanup_hostwide(). >> >> Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com> >> --- >> arch/powerpc/kvm/book3s_hv_pmu.c | 189 +++++++++++++++++++++++++++++++ >> 1 file changed, 189 insertions(+) >> >> diff --git a/arch/powerpc/kvm/book3s_hv_pmu.c b/arch/powerpc/kvm/book3s_hv_pmu.c >> index e72542d5e750..f7fd5190ecf7 100644 >> --- a/arch/powerpc/kvm/book3s_hv_pmu.c >> +++ b/arch/powerpc/kvm/book3s_hv_pmu.c >> @@ -27,10 +27,31 @@ >> #include <asm/plpar_wrappers.h> >> #include <asm/firmware.h> >> >> +#include "asm/guest-state-buffer.h" >> + >> enum kvmppc_pmu_eventid { >> KVMPPC_EVENT_MAX, >> }; >> >> +#define KVMPPC_PMU_EVENT_ATTR(_name, _id) \ >> + PMU_EVENT_ATTR_ID(_name, power_events_sysfs_show, _id) >> + >> +/* Holds the hostwide stats */ >> +static struct kvmppc_hostwide_stats { >> + u64 guest_heap; >> + u64 guest_heap_max; >> + u64 guest_pgtable_size; >> + u64 guest_pgtable_size_max; >> + u64 guest_pgtable_reclaim; >> +} l0_stats; >> + >> +/* Protect access to l0_stats */ >> +static DEFINE_SPINLOCK(lock_l0_stats); >> + >> +/* GSB related structs needed to talk to L0 */ >> +static struct kvmppc_gs_msg *gsm_l0_stats; >> +static struct kvmppc_gs_buff *gsb_l0_stats; >> + >> static struct attribute *kvmppc_pmu_events_attr[] = { >> NULL, >> }; >> @@ -90,6 +111,167 @@ static void kvmppc_pmu_read(struct perf_event *event) >> { >> } >> >> +/* Return the size of the needed guest state buffer */ >> +static size_t hostwide_get_size(struct kvmppc_gs_msg *gsm) >> + >> +{ >> + size_t size = 0; >> + const u16 ids[] = { >> + KVMPPC_GSID_L0_GUEST_HEAP, >> + KVMPPC_GSID_L0_GUEST_HEAP_MAX, >> + KVMPPC_GSID_L0_GUEST_PGTABLE_SIZE, >> + KVMPPC_GSID_L0_GUEST_PGTABLE_SIZE_MAX, >> + KVMPPC_GSID_L0_GUEST_PGTABLE_RECLAIM >> + }; >> + >> + for (int i = 0; i < ARRAY_SIZE(ids); i++) >> + size += kvmppc_gse_total_size(kvmppc_gsid_size(ids[i])); >> + return size; >> +} >> + >> +/* Populate the request guest state buffer */ >> +static int hostwide_fill_info(struct kvmppc_gs_buff *gsb, >> + struct kvmppc_gs_msg *gsm) >> +{ >> + struct kvmppc_hostwide_stats *stats = gsm->data; >> + >> + /* >> + * It doesn't matter what values are put into request buffer as >> + * they are going to be overwritten anyways. But for the sake of >> + * testcode and symmetry contents of existing stats are put >> + * populated into the request guest state buffer. >> + */ >> + if (kvmppc_gsm_includes(gsm, KVMPPC_GSID_L0_GUEST_HEAP)) >> + kvmppc_gse_put_u64(gsb, KVMPPC_GSID_L0_GUEST_HEAP, >> + stats->guest_heap); >> + if (kvmppc_gsm_includes(gsm, KVMPPC_GSID_L0_GUEST_HEAP_MAX)) >> + kvmppc_gse_put_u64(gsb, KVMPPC_GSID_L0_GUEST_HEAP_MAX, >> + stats->guest_heap_max); >> + if (kvmppc_gsm_includes(gsm, KVMPPC_GSID_L0_GUEST_PGTABLE_SIZE)) >> + kvmppc_gse_put_u64(gsb, KVMPPC_GSID_L0_GUEST_PGTABLE_SIZE, >> + stats->guest_pgtable_size); >> + if (kvmppc_gsm_includes(gsm, KVMPPC_GSID_L0_GUEST_PGTABLE_SIZE_MAX)) >> + kvmppc_gse_put_u64(gsb, KVMPPC_GSID_L0_GUEST_PGTABLE_SIZE_MAX, >> + stats->guest_pgtable_size_max); >> + if (kvmppc_gsm_includes(gsm, KVMPPC_GSID_L0_GUEST_PGTABLE_RECLAIM)) >> + kvmppc_gse_put_u64(gsb, KVMPPC_GSID_L0_GUEST_PGTABLE_RECLAIM, >> + stats->guest_pgtable_reclaim); >> + >> + return 0; >> +} > > kvmppc_gse_put_u64() can return an error. I think we can handle it just > like gs_msg_ops_vcpu_fill_info() > Good suggestion. Will incorporate that in v2. >> + >> +/* Parse and update the host wide stats from returned gsb */ >> +static int hostwide_refresh_info(struct kvmppc_gs_msg *gsm, >> + struct kvmppc_gs_buff *gsb) >> +{ >> + struct kvmppc_gs_parser gsp = { 0 }; >> + struct kvmppc_hostwide_stats *stats = gsm->data; >> + struct kvmppc_gs_elem *gse; >> + int rc; >> + >> + rc = kvmppc_gse_parse(&gsp, gsb); >> + if (rc < 0) >> + return rc; >> + >> + gse = kvmppc_gsp_lookup(&gsp, KVMPPC_GSID_L0_GUEST_HEAP); >> + if (gse) >> + stats->guest_heap = kvmppc_gse_get_u64(gse); >> + >> + gse = kvmppc_gsp_lookup(&gsp, KVMPPC_GSID_L0_GUEST_HEAP_MAX); >> + if (gse) >> + stats->guest_heap_max = kvmppc_gse_get_u64(gse); >> + >> + gse = kvmppc_gsp_lookup(&gsp, KVMPPC_GSID_L0_GUEST_PGTABLE_SIZE); >> + if (gse) >> + stats->guest_pgtable_size = kvmppc_gse_get_u64(gse); >> + >> + gse = kvmppc_gsp_lookup(&gsp, KVMPPC_GSID_L0_GUEST_PGTABLE_SIZE_MAX); >> + if (gse) >> + stats->guest_pgtable_size_max = kvmppc_gse_get_u64(gse); >> + >> + gse = kvmppc_gsp_lookup(&gsp, KVMPPC_GSID_L0_GUEST_PGTABLE_RECLAIM); >> + if (gse) >> + stats->guest_pgtable_reclaim = kvmppc_gse_get_u64(gse); >> + >> + return 0; >> +} >> + >> +/* gsb-message ops for setting up/parsing */ >> +static struct kvmppc_gs_msg_ops gsb_ops_l0_stats = { >> + .get_size = hostwide_get_size, >> + .fill_info = hostwide_fill_info, >> + .refresh_info = hostwide_refresh_info, >> +}; >> + >> +static int kvmppc_init_hostwide(void) >> +{ >> + int rc = 0; >> + unsigned long flags; >> + >> + spin_lock_irqsave(&lock_l0_stats, flags); >> + >> + /* already registered ? */ >> + if (gsm_l0_stats) { >> + rc = 0; >> + goto out; >> + } >> + >> + /* setup the Guest state message/buffer to talk to L0 */ >> + gsm_l0_stats = kvmppc_gsm_new(&gsb_ops_l0_stats, &l0_stats, >> + GSM_SEND, GFP_KERNEL); >> + if (!gsm_l0_stats) { >> + rc = -ENOMEM; >> + goto out; >> + } >> + >> + /* Populate the Idents */ >> + kvmppc_gsm_include(gsm_l0_stats, KVMPPC_GSID_L0_GUEST_HEAP); >> + kvmppc_gsm_include(gsm_l0_stats, KVMPPC_GSID_L0_GUEST_HEAP_MAX); >> + kvmppc_gsm_include(gsm_l0_stats, KVMPPC_GSID_L0_GUEST_PGTABLE_SIZE); >> + kvmppc_gsm_include(gsm_l0_stats, KVMPPC_GSID_L0_GUEST_PGTABLE_SIZE_MAX); >> + kvmppc_gsm_include(gsm_l0_stats, KVMPPC_GSID_L0_GUEST_PGTABLE_RECLAIM); >> + >> + /* allocate GSB. Guest/Vcpu Id is ignored */ >> + gsb_l0_stats = kvmppc_gsb_new(kvmppc_gsm_size(gsm_l0_stats), 0, 0, >> + GFP_KERNEL); >> + if (!gsb_l0_stats) { >> + rc = -ENOMEM; >> + goto out; >> + } >> + >> + /* ask the ops to fill in the info */ >> + rc = kvmppc_gsm_fill_info(gsm_l0_stats, gsb_l0_stats); >> + if (rc) >> + goto out; >> +out: >> + if (rc) { >> + if (gsm_l0_stats) >> + kvmppc_gsm_free(gsm_l0_stats); >> + if (gsb_l0_stats) >> + kvmppc_gsb_free(gsb_l0_stats); >> + gsm_l0_stats = NULL; >> + gsb_l0_stats = NULL; >> + } >> + spin_unlock_irqrestore(&lock_l0_stats, flags); >> + return rc; >> +} > > The error handling can probably be simplified to avoid multiple ifs: > > <snip> > > /* allocate GSB. Guest/Vcpu Id is ignored */ > gsb_l0_stats = kvmppc_gsb_new(kvmppc_gsm_size(gsm_l0_stats), 0, 0, > GFP_KERNEL); > if (!gsb_l0_stats) { > rc = -ENOMEM; > goto err_gsm; > } > > /* ask the ops to fill in the info */ > rc = kvmppc_gsm_fill_info(gsm_l0_stats, gsb_l0_stats); > if (!rc) > goto out; > > err_gsb: > kvmppc_gsb_free(gsb_l0_stats); > gsb_l0_stats = NULL; > > err_gsm: > kvmppc_gsm_free(gsm_l0_stats); > gsm_l0_stats = NULL; > > out: > spin_unlock_irqrestore(&lock_l0_stats, flags); > return rc; > } > Thats subjective opinion and I tend to prefer less number of goto jump labels in the function hence the function is implemented the way it is. >> + >> +static void kvmppc_cleanup_hostwide(void) >> +{ >> + unsigned long flags; >> + >> + spin_lock_irqsave(&lock_l0_stats, flags); >> + >> + if (gsm_l0_stats) >> + kvmppc_gsm_free(gsm_l0_stats); >> + if (gsb_l0_stats) >> + kvmppc_gsb_free(gsb_l0_stats); >> + gsm_l0_stats = NULL; >> + gsb_l0_stats = NULL; >> + >> + spin_unlock_irqrestore(&lock_l0_stats, flags); >> +} >> + >> /* L1 wide counters PMU */ >> static struct pmu kvmppc_pmu = { >> .task_ctx_nr = perf_sw_context, >> @@ -108,6 +290,10 @@ int kvmppc_register_pmu(void) >> >> /* only support events for nestedv2 right now */ >> if (kvmhv_is_nestedv2()) { >> + rc = kvmppc_init_hostwide(); >> + if (rc) >> + goto out; >> + >> /* Setup done now register the PMU */ >> pr_info("Registering kvm-hv pmu"); >> >> @@ -117,6 +303,7 @@ int kvmppc_register_pmu(void) >> -1) : 0; >> } >> >> +out: >> return rc; >> } >> EXPORT_SYMBOL_GPL(kvmppc_register_pmu); >> @@ -124,6 +311,8 @@ EXPORT_SYMBOL_GPL(kvmppc_register_pmu); >> void kvmppc_unregister_pmu(void) >> { >> if (kvmhv_is_nestedv2()) { >> + kvmppc_cleanup_hostwide(); >> + >> if (kvmppc_pmu.type != -1) >> perf_pmu_unregister(&kvmppc_pmu); >> >> -- >> 2.47.1 >>
diff --git a/arch/powerpc/kvm/book3s_hv_pmu.c b/arch/powerpc/kvm/book3s_hv_pmu.c index e72542d5e750..f7fd5190ecf7 100644 --- a/arch/powerpc/kvm/book3s_hv_pmu.c +++ b/arch/powerpc/kvm/book3s_hv_pmu.c @@ -27,10 +27,31 @@ #include <asm/plpar_wrappers.h> #include <asm/firmware.h> +#include "asm/guest-state-buffer.h" + enum kvmppc_pmu_eventid { KVMPPC_EVENT_MAX, }; +#define KVMPPC_PMU_EVENT_ATTR(_name, _id) \ + PMU_EVENT_ATTR_ID(_name, power_events_sysfs_show, _id) + +/* Holds the hostwide stats */ +static struct kvmppc_hostwide_stats { + u64 guest_heap; + u64 guest_heap_max; + u64 guest_pgtable_size; + u64 guest_pgtable_size_max; + u64 guest_pgtable_reclaim; +} l0_stats; + +/* Protect access to l0_stats */ +static DEFINE_SPINLOCK(lock_l0_stats); + +/* GSB related structs needed to talk to L0 */ +static struct kvmppc_gs_msg *gsm_l0_stats; +static struct kvmppc_gs_buff *gsb_l0_stats; + static struct attribute *kvmppc_pmu_events_attr[] = { NULL, }; @@ -90,6 +111,167 @@ static void kvmppc_pmu_read(struct perf_event *event) { } +/* Return the size of the needed guest state buffer */ +static size_t hostwide_get_size(struct kvmppc_gs_msg *gsm) + +{ + size_t size = 0; + const u16 ids[] = { + KVMPPC_GSID_L0_GUEST_HEAP, + KVMPPC_GSID_L0_GUEST_HEAP_MAX, + KVMPPC_GSID_L0_GUEST_PGTABLE_SIZE, + KVMPPC_GSID_L0_GUEST_PGTABLE_SIZE_MAX, + KVMPPC_GSID_L0_GUEST_PGTABLE_RECLAIM + }; + + for (int i = 0; i < ARRAY_SIZE(ids); i++) + size += kvmppc_gse_total_size(kvmppc_gsid_size(ids[i])); + return size; +} + +/* Populate the request guest state buffer */ +static int hostwide_fill_info(struct kvmppc_gs_buff *gsb, + struct kvmppc_gs_msg *gsm) +{ + struct kvmppc_hostwide_stats *stats = gsm->data; + + /* + * It doesn't matter what values are put into request buffer as + * they are going to be overwritten anyways. But for the sake of + * testcode and symmetry contents of existing stats are put + * populated into the request guest state buffer. + */ + if (kvmppc_gsm_includes(gsm, KVMPPC_GSID_L0_GUEST_HEAP)) + kvmppc_gse_put_u64(gsb, KVMPPC_GSID_L0_GUEST_HEAP, + stats->guest_heap); + if (kvmppc_gsm_includes(gsm, KVMPPC_GSID_L0_GUEST_HEAP_MAX)) + kvmppc_gse_put_u64(gsb, KVMPPC_GSID_L0_GUEST_HEAP_MAX, + stats->guest_heap_max); + if (kvmppc_gsm_includes(gsm, KVMPPC_GSID_L0_GUEST_PGTABLE_SIZE)) + kvmppc_gse_put_u64(gsb, KVMPPC_GSID_L0_GUEST_PGTABLE_SIZE, + stats->guest_pgtable_size); + if (kvmppc_gsm_includes(gsm, KVMPPC_GSID_L0_GUEST_PGTABLE_SIZE_MAX)) + kvmppc_gse_put_u64(gsb, KVMPPC_GSID_L0_GUEST_PGTABLE_SIZE_MAX, + stats->guest_pgtable_size_max); + if (kvmppc_gsm_includes(gsm, KVMPPC_GSID_L0_GUEST_PGTABLE_RECLAIM)) + kvmppc_gse_put_u64(gsb, KVMPPC_GSID_L0_GUEST_PGTABLE_RECLAIM, + stats->guest_pgtable_reclaim); + + return 0; +} + +/* Parse and update the host wide stats from returned gsb */ +static int hostwide_refresh_info(struct kvmppc_gs_msg *gsm, + struct kvmppc_gs_buff *gsb) +{ + struct kvmppc_gs_parser gsp = { 0 }; + struct kvmppc_hostwide_stats *stats = gsm->data; + struct kvmppc_gs_elem *gse; + int rc; + + rc = kvmppc_gse_parse(&gsp, gsb); + if (rc < 0) + return rc; + + gse = kvmppc_gsp_lookup(&gsp, KVMPPC_GSID_L0_GUEST_HEAP); + if (gse) + stats->guest_heap = kvmppc_gse_get_u64(gse); + + gse = kvmppc_gsp_lookup(&gsp, KVMPPC_GSID_L0_GUEST_HEAP_MAX); + if (gse) + stats->guest_heap_max = kvmppc_gse_get_u64(gse); + + gse = kvmppc_gsp_lookup(&gsp, KVMPPC_GSID_L0_GUEST_PGTABLE_SIZE); + if (gse) + stats->guest_pgtable_size = kvmppc_gse_get_u64(gse); + + gse = kvmppc_gsp_lookup(&gsp, KVMPPC_GSID_L0_GUEST_PGTABLE_SIZE_MAX); + if (gse) + stats->guest_pgtable_size_max = kvmppc_gse_get_u64(gse); + + gse = kvmppc_gsp_lookup(&gsp, KVMPPC_GSID_L0_GUEST_PGTABLE_RECLAIM); + if (gse) + stats->guest_pgtable_reclaim = kvmppc_gse_get_u64(gse); + + return 0; +} + +/* gsb-message ops for setting up/parsing */ +static struct kvmppc_gs_msg_ops gsb_ops_l0_stats = { + .get_size = hostwide_get_size, + .fill_info = hostwide_fill_info, + .refresh_info = hostwide_refresh_info, +}; + +static int kvmppc_init_hostwide(void) +{ + int rc = 0; + unsigned long flags; + + spin_lock_irqsave(&lock_l0_stats, flags); + + /* already registered ? */ + if (gsm_l0_stats) { + rc = 0; + goto out; + } + + /* setup the Guest state message/buffer to talk to L0 */ + gsm_l0_stats = kvmppc_gsm_new(&gsb_ops_l0_stats, &l0_stats, + GSM_SEND, GFP_KERNEL); + if (!gsm_l0_stats) { + rc = -ENOMEM; + goto out; + } + + /* Populate the Idents */ + kvmppc_gsm_include(gsm_l0_stats, KVMPPC_GSID_L0_GUEST_HEAP); + kvmppc_gsm_include(gsm_l0_stats, KVMPPC_GSID_L0_GUEST_HEAP_MAX); + kvmppc_gsm_include(gsm_l0_stats, KVMPPC_GSID_L0_GUEST_PGTABLE_SIZE); + kvmppc_gsm_include(gsm_l0_stats, KVMPPC_GSID_L0_GUEST_PGTABLE_SIZE_MAX); + kvmppc_gsm_include(gsm_l0_stats, KVMPPC_GSID_L0_GUEST_PGTABLE_RECLAIM); + + /* allocate GSB. Guest/Vcpu Id is ignored */ + gsb_l0_stats = kvmppc_gsb_new(kvmppc_gsm_size(gsm_l0_stats), 0, 0, + GFP_KERNEL); + if (!gsb_l0_stats) { + rc = -ENOMEM; + goto out; + } + + /* ask the ops to fill in the info */ + rc = kvmppc_gsm_fill_info(gsm_l0_stats, gsb_l0_stats); + if (rc) + goto out; +out: + if (rc) { + if (gsm_l0_stats) + kvmppc_gsm_free(gsm_l0_stats); + if (gsb_l0_stats) + kvmppc_gsb_free(gsb_l0_stats); + gsm_l0_stats = NULL; + gsb_l0_stats = NULL; + } + spin_unlock_irqrestore(&lock_l0_stats, flags); + return rc; +} + +static void kvmppc_cleanup_hostwide(void) +{ + unsigned long flags; + + spin_lock_irqsave(&lock_l0_stats, flags); + + if (gsm_l0_stats) + kvmppc_gsm_free(gsm_l0_stats); + if (gsb_l0_stats) + kvmppc_gsb_free(gsb_l0_stats); + gsm_l0_stats = NULL; + gsb_l0_stats = NULL; + + spin_unlock_irqrestore(&lock_l0_stats, flags); +} + /* L1 wide counters PMU */ static struct pmu kvmppc_pmu = { .task_ctx_nr = perf_sw_context, @@ -108,6 +290,10 @@ int kvmppc_register_pmu(void) /* only support events for nestedv2 right now */ if (kvmhv_is_nestedv2()) { + rc = kvmppc_init_hostwide(); + if (rc) + goto out; + /* Setup done now register the PMU */ pr_info("Registering kvm-hv pmu"); @@ -117,6 +303,7 @@ int kvmppc_register_pmu(void) -1) : 0; } +out: return rc; } EXPORT_SYMBOL_GPL(kvmppc_register_pmu); @@ -124,6 +311,8 @@ EXPORT_SYMBOL_GPL(kvmppc_register_pmu); void kvmppc_unregister_pmu(void) { if (kvmhv_is_nestedv2()) { + kvmppc_cleanup_hostwide(); + if (kvmppc_pmu.type != -1) perf_pmu_unregister(&kvmppc_pmu);
Implement and setup necessary structures to send a prepolulated Guest-State-Buffer(GSB) requesting hostwide counters to L0-PowerVM and have the returned GSB holding the values of these counters parsed. This is done via existing GSB implementation and with the newly added support of Hostwide elements in GSB. The request to L0-PowerVM to return Hostwide counters is done using a pre-allocated GSB named 'gsb_l0_stats'. To be able to populate this GSB with the needed Guest-State-Elements (GSIDs) a instance of 'struct kvmppc_gs_msg' named 'gsm_l0_stats' is introduced. The 'gsm_l0_stats' is tied to an instance of 'struct kvmppc_gs_msg_ops' named 'gsb_ops_l0_stats' which holds various callbacks to be compute the size ( hostwide_get_size() ), populate the GSB ( hostwide_fill_info() ) and refresh ( hostwide_refresh_info() ) the contents of 'l0_stats' that holds the Hostwide counters returned from L0-PowerVM. To protect these structures from simultaneous access a spinlock 'lock_l0_stats' has been introduced. The allocation and initialization of the above structures is done in newly introduced kvmppc_init_hostwide() and similarly the cleanup is performed in newly introduced kvmppc_cleanup_hostwide(). Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com> --- arch/powerpc/kvm/book3s_hv_pmu.c | 189 +++++++++++++++++++++++++++++++ 1 file changed, 189 insertions(+)